Trigger Port Forwarding; Figure 30-20 Example 4: Menu 15.1.1.1: Address Mapping Rule; Figure 30-21 Example 4: Menu 15.1.1: Address Mapping Rules - ZyXEL Communications ZyWALL 5 User Manual

Press ENTER to Confirm or ESC to Cancel:

Figure 30-20 Example 4: Menu 15.1.1.1: Address Mapping Rule

After you've configured your rule, you should be able to check the settings in menu 15.1.1 as shown
next.
Set Name= Example4
Idx Local Start IP
--- ---------------
1. 192.168.1.10
2.
3.
4.
5.
6.
7.
8.
9.
10.

Figure 30-21 Example 4: Menu 15.1.1: Address Mapping Rules

30.5 Trigger Port Forwarding

Some services use a dedicated range of ports on the client side and a dedicated range of ports on the
server side. With regular port forwarding you set a forwarding port in NAT to forward a service
(coming in from the server on the WAN) to the IP address of a computer on the client side (LAN). The
problem is that port forwarding only forwards a service to a single LAN IP address. In order to use the
same service on a different LAN computer, you have to manually replace the LAN computer's IP
address in the forwarding port with another LAN computer's IP address.
Trigger port forwarding solves this problem by allowing computers on the LAN to dynamically take
turns using the service. The ZyWALL records the IP address of a LAN computer that sends traffic to
the WAN to request a service with a specific port number and protocol (a "trigger" port). When the
ZyWALL's WAN port receives a response with a specific port number and protocol ("incoming" port),
the ZyWALL forwards the traffic to the LAN IP address of the computer that sent the request. After
NAT
Menu 15.1.1.1 Address Mapping Rule
Type= Many-One-to-One
Local IP:
Start= 192.168.1.10
End = 192.168.1.12
Global IP:
Start= 10.132.50.1
End = 10.132.50.3
Menu 15.1.1 - Address Mapping Rules
Local End IP
---------------
192.168.1.12
Action= Edit
Press ENTER to Confirm or ESC to Cancel:
ZyWALL 5 Internet Security Appliance
Global Start IP Global End IP
--------------- ---------------
10.132.50.1 10.132.50.3
Select Rule=
Type
------
M-1-1
30-13